I use a a su vide (circulator) to void scorching. This is a culinary tool. The unit is used to heat the mash water and maintain the temperature during the mash. Since the heating element is contained in the unit it never makes contact with the bag. Works like a charm.
The equipment total is the su vide, brew bag and pot that you also boil in.
The equipment total is the su vide, brew bag and pot that you also boil in.